• Otvos, Imre S.
  Newfoundland Forest Research Centre
  
• Raske, Arthur G.
  Newfoundland Forest Research Centre
  

The effect of aerial application of fenitrothion, Matacil, either alone or in combination, and Bacillus thuringiensis plus Orthene on the two major larval parasites of the spruce budworm (Choristoneura fumiferana) was investigated. None of the spray regimes had significant effect on the rate of parasitism by the two major larval parasites. There was a slightly higher incidence of parasitism by both Apanteles fumiferanae and Glyptta fumiferance in most treated blockers that in the control blocks. These differences are not significant, and may be due to the behavior of the parasitized host larvae.